1. Field of the Invention
The present invention relates to an emulsion ink for stencil printing. Specifically, it relates to an emulsion ink for stencil printing excellent in its drying property, sticking tendency and preservation stability and suitable for adding its building-up feeling and brilliance to the printed letters and others.
2. Description of the Prior Art
A stencil printing method has been utilized in a very extensive range of fields because of the easiness in preparing a stencil sheet. The process for drying the ink in stencil printing is normally proceeded by the permeation of an ink emulsion into a printing paper and the evaporation of the moisture contained in the ink emulsion. Therefore, it has been impossible to completely stick the ink to a printing paper since the drying process proceeds only by the evaporation of the moisture from the ink emulsion on the printing body such as a high quality paper, i.e., a coated paper which has no permeability at all, or a film.
On the other hand, in the case that a permeative material is used as a body to be printed on, the ink permeates into the inside of the body to be printed on. As a result, it is very hard to give the building-up feeling and brilliance to the printed letters and others. Further, and there is a disadvantage in that the resulting set-off is easily caused at the time of continuous printing due to the delay in its permeation velocity.
As a method for improving the drying property of the stencil printing ink, there is known a method which uses an oil-in-water type emulsion ink, the oil phase of which includes a resin component of a polymer type such as an oxidation polymerization product. It was impossible, however, to leave it for many hours due to the generation of plugging-up of the ink in the stencil sheet and the resulting handling became very troublesome due to the inferior preservation stability of the emulsion ink.